1. Field of the Invention
The present invention pertains to an apparatus for interconnecting a tubing string with a downhole well tool and which includes an inflatable packer and a fluid flow control valve for controlling the flow of fluid to inflate the packer and for injection of fluids into the wellbore.
2. Background
The development of downhole well tools and instruments for determining the characteristics of subterranean formations has become an important process in producing hydrocarbons from subterranean reservoirs. Many operations require the deployment of electrically operated tools and instruments in the wellbore and hence an electrical multiconductor cable is required for the transmission of signals between the tool and a srrface control unit or data recording system, such cables sometimes referred to as "wirelines."
In certain types of operations involving dcwnhole electrical tools and instruments, it is advantageous and often necessary to convey such apparatus into and out of the wellbore connected to an elongated tubing string which may be of a type sometimes referred to as "coiled tubing." The wireline cable is typically run within the tubing string to the tool or instrument and the tubing string is utilized to inject certain fluids into a zone of interest penetrated by the wellbore.
With these types of operations in mind, there has been a need to provide an apparatus which is able to control the flow of fluids into and out of the wellbore, provide for sealing or packing off of the zone of interest to be injected with fluid or to be measured for pressure and fluid flow characteristics and which is adapted to be interposed between the tool and the tubing string. It is to this end that the present invention has been developed.